The Moon moves through 4 primary phases each month, new, first quarter, full, and last quarter, and the complete cycle repeats roughly every 29.5 days, according to the US Naval Observatory’s Astronomical Applications Department. Traditional almanac gardening assigns a different planting task to each half of that cycle rather than to a single calendar date, so the pattern below works the same regardless of which month you check it against, inside the almanac wisdom framework this pillar tracks alongside frost dates and folklore signs.
Best Days to Plant by the Moon Phase by Phase
The Old Farmer’s Almanac, the historical almanac publication that records this practice, names four points in the cycle: new moon, first quarter (the waxing midpoint), full moon, and last quarter (the waning midpoint). Its published version simplifies those four points into two working arcs: the roughly two-week stretch from new moon to full moon, called waxing, and the roughly two-week stretch from full moon back to new moon, called waning. Each arc is assigned to a different category of crop, covered in the table further down this page. Because the new moon and full moon are single published instants, not date ranges, the two arcs between them are what a gardener actually plants around, not one isolated “best day.”
This is tradition, not a demonstrated outcome. This page describes a folk gardening practice recorded in historical almanacs. Its windows are reported as tradition, not as a measured result: no source cited here shows that timing a planting to the Moon’s phase changes how a seed germinates or a plant develops.
How Long Does the Waxing Moon Phase Last Each Month
The waxing half of the cycle, from new moon to full moon, runs about two weeks. The US Naval Observatory’s Astronomical Applications Department states that each of the Moon’s four intermediate phases, waxing crescent, waxing gibbous, waning gibbous, and waning crescent, “lasts for about a week between the primary phases.” New moon to full moon crosses two of those, waxing crescent then waxing gibbous, so about a week plus about a week works out to roughly two weeks. That figure is an approximation, not a fixed count: the Moon’s orbital speed varies through its elliptical orbit, so the exact interval between primary phases shifts slightly month to month. For an exact count in a given month, USNO’s Dates of Primary Phases of the Moon tool, useful for anyone checking how far the exact new moon and full moon dates shift from year to year, covers any year between 1700 and 2100.
How Many Best Planting Days Fall in a Typical Month
“Moon planting” actually names two different systems that routinely get treated as one. An astronomical version tracks phase alone, the roughly two-week waxing and waning arcs described above, with no single date set aside as better than another inside the arc. An astrological version adds the Moon’s position against the zodiac and narrows those arcs down to specific dated days. Both the Old Farmer’s Almanac and the Farmers’ Almanac publish the zodiac-based version: the Old Farmer’s Almanac runs it as a dated Best Days timetable, published in separate above-ground and below-ground pages, calculated from Moon phase together with zodiac sign, not phase alone. Its own separate explainer page on planting by the Moon draws roughly that same line itself, distinguishing the astronomical practice of planting by the Moon’s phase from the astrological “Best Days” version most readers mean by the term, and pointing readers to its own Best Days timetable for that version. This page describes the phase-only, astronomical version, because it maps onto a repeating pattern rather than a list of dates that changes every month; a reader who wants the zodiac-based dated list should go to the source’s own Best Days pages directly, not this table. That is the real distinction behind a “best days” count that seems to differ between sources: usually it is two different systems being compared, not two publishers disagreeing. Splitting the 29.5-day cycle evenly across the two phase-only arcs works out to roughly 14 to 15 days per half, arithmetic drawn from USNO’s published cycle length rather than a count either almanac states directly for the phase-only version.
What Happens If You Plant Outside the Traditional Moon-Phase Window
No extension source or agronomic study checked for this article compares planting-date outcomes for crops timed to a lunar phase against crops planted on any other day. That absence runs both ways: it is not evidence that ignoring the window causes a problem, and not evidence that following it produces a better result. USDA and state university extension planting-date guidance is built on frost date and soil temperature, tracked through NOAA/NWS climate normals. A gardener following a frost-date calendar and one also tracking moon phase are working from two calendars built on entirely different evidence.
This Month’s Best Days to Plant by the Moon, Phase by Phase
This table carries the repeating four-phase pattern rather than a specific month’s dates, since the exact new moon and full moon dates move every month. Look up your own month using the procedure below the table.
Moon Phase Planting Windows by Phase
| Phase | How long it runs | Traditionally assigned to (Old Farmer’s Almanac) | Status |
|---|---|---|---|
| New moon | A single published instant, not a range; opens the waxing arc | Marks the start of the above-ground planting window | Traditional belief, not tested results |
| Waxing (new moon to full moon) | About two weeks (two roughly week-long intermediate phases, per USNO) | Above-ground annual flowers and food crops. Old Farmer’s Almanac’s own examples: “corn, tomatoes, watermelon, and zucchini” | Traditional belief, not tested results |
| Full moon | A single published instant, not a range; opens the waning arc | Marks the start of the below-ground planting window | Traditional belief, not tested results |
| Waning (full moon to new moon) | About two weeks (two roughly week-long intermediate phases, per USNO) | Below-ground vegetables, plus flowering bulbs and biennial and perennial flowers as a separate named category. Old Farmer’s Almanac’s own examples for the vegetables: “carrots, onions, and potatoes” | Traditional belief, not tested results |
To apply this pattern to the month you are in, look up the exact new moon and full moon dates using USNO’s Dates of Primary Phases of the Moon tool (any year, 1700 to 2100) or NASA’s daily Moon-phase pages. Count forward from the new moon toward the full moon for the above-ground window, and from the full moon toward the next new moon for the below-ground window. Because the full cycle averages 29.5 days and does not split into two exactly equal halves every month, treat the two-week figure as a working approximation.
What ‘Above-Ground’ and ‘Below-Ground’ Crops Mean in Moon Planting
“Above-ground” and “below-ground” are this tradition’s own labels, not a botanical classification, and they sort crops by which part the gardener is growing it for, not by where the plant’s tissue sits in the soil. Zucchini, watermelon, tomatoes, and corn fall on the Old Farmer’s Almanac’s above-ground list, crops grown for a fruit, seed head, or leaf that develops above the soil line, planted during the waxing arc. Potatoes, onions, and carrots fall on its below-ground list, alongside flowering bulbs and biennial and perennial flowers, planted during the waning arc. The category can cut against a plant’s own anatomy: a potato plant grows leaves and stems above ground the same as a tomato plant does, but the tradition sorts the potato by the tuber it is grown for, not by its foliage. That distinction matters before comparing this tradition to a botanical classification, which groups plants by growth habit or life cycle instead.
Sow, Plant, or Transplant by the Moon: Which Verb Applies
The Old Farmer’s Almanac’s own moon-phase guidance uses a single verb, “plant,” across both halves of the cycle, without separately addressing sowing seed directly versus transplanting a seedling started earlier indoors. In general garden usage, sowing means placing seed directly where it will grow, and transplanting means moving an already-started seedling into its permanent bed. Because the sourced version of this tradition does not carry that distinction, the more defensible reading is that its phase windows apply to whichever action puts the plant or seed into position for the season, direct-sown or transplanted, rather than one narrow technique. Readers working from a more detailed almanac source should check whether it specifies sowing, transplanting, or setting out separately, since not every publication uses the single verb the Old Farmer’s Almanac does.
Why Some Growers Say the Best Days Never Line Up With Their Weather
Whether or not a given grower has said as much, there is a structural reason a moon-phase window and local weather would drift apart instead of lining up. The lunar cycle is fixed and astronomical: USNO’s published 29.5-day average duration does not shift by region, elevation, or year. Frost dates, soil temperature, and rainfall are none of those things. NOAA/NCEI’s 1991-2020 US Climate Normals, the source behind this site’s own frost-date lookup, put growing-season length at roughly 149 days at the Anchorage station and a virtually year-round season at the Phoenix, Orlando, and Honolulu stations. Because the Moon’s phases repeat on the same schedule everywhere, while the local frost date, soil-warming date, and rain pattern that govern germination vary by hundreds of miles, the two calendars drift apart by construction, not by exception. A window that lines up with workable soil in one region and year can land on frozen or waterlogged ground in another, because nothing ties the lunar calendar to local conditions.
Last verified: 2026-08-15. Sources checked: USNO’s Moon-phase FAQ and Dates of Primary Phases tool, NASA’s Moon-phase pages, the Old Farmer’s Almanac’s Planting by the Moon explainer and its Best Days above-ground and below-ground pages, the Farmers’ Almanac, the Biodynamic Association, and NOAA/NCEI’s US Climate Normals.
Frequently Asked Questions
Do professional farmers actually use moon planting calendars? US extension planting-date guidance is built on frost dates and soil temperature, tracked through NOAA/NWS normals, not the Moon’s phase. Moon-phase planting is documented mainly in home-garden and historical-almanac sources such as the Old Farmer’s Almanac and the Farmers’ Almanac. No adoption figure for farmers or gardeners is grounded in the sources checked for this article.
Is moon phase planting the same thing as biodynamic gardening? No. Biodynamic gardening is a separate, named philosophy with its own certification process, tracked by the Biodynamic Association, working from a broader calendar system beyond the Moon’s four phases. The above-ground and below-ground pattern on this page is the simpler, phase-only version published by the Old Farmer’s Almanac.
Does a full moon mean I should skip planting that day? No. In the Old Farmer’s Almanac’s version of this tradition, the full moon is the pivot point that opens the below-ground planting arc, not a day to avoid. The new moon plays the same pivot role for the above-ground arc; neither instant is a rest day.
How far ahead can I find next month’s best planting days? The US Naval Observatory’s Dates of Primary Phases of the Moon tool calculates the exact new moon and full moon dates for any year between 1700 and 2100. NASA’s Moon-phase pages cover near-term dates the same way.
Is the moon planting calendar the same in the Southern Hemisphere? For practical purposes, the phases of the Moon are independent of the location on Earth from which they are observed, since they are defined by the Moon and Sun’s positions in the sky, per the US Naval Observatory. What differs is the growing season, inverted between hemispheres, so the same phase rule lands on opposite calendar months.
Sources
- US Naval Observatory, Astronomical Applications Department: Phases of the Moon FAQ
- US Naval Observatory: Dates of Primary Phases of the Moon
- NASA Science: Moon Phases
- Old Farmer’s Almanac: Planting by the Moon
- Old Farmer’s Almanac: Best Days to Plant Above-Ground Crops
- Old Farmer’s Almanac: Best Days to Plant Below-Ground Crops
- Farmers’ Almanac: Best Days Calendar
- Biodynamic Association
- NOAA/NCEI: US Climate Normals
Last verified: 2026-08-15, against US Naval Observatory, NASA Science, Old Farmer’s Almanac, Farmers’ Almanac, Biodynamic Association and NOAA/NCEI.